Persistent Map Vote Tallies (#86788)

## About The Pull Request

Changes map votes to be based on a persistent tally count.
Tallies for maps are cached between rounds and are added to by map
votes.
When a map is chosen, and it wasn't the only valid one, the tallies for
said chosen map will be reset.

Refactors map vote handling and moves it from SSmapping to SSmap_vote.
Rock the Vote has been removed as a result of this refactor.

## Why It's Good For The Game

Makes it more likely that all maps will be played over the course of a
server instead of always being truly random.
Removes some clutter off of SSmapping.

🆑
refactor: Map Votes are now carried over between rounds. When a map vote
is actually a contest, the winning map will have its votes reset.
/🆑

code/modules/shuttle/shuttle.dm

@@ -264,7 +264,7 @@
 
 /obj/docking_port/stationary/proc/load_roundstart()
 	if(json_key)
-		var/sid = SSmapping.config.shuttles[json_key]
+		var/sid = SSmapping.current_map.shuttles[json_key]
 		roundstart_template = SSmapping.shuttle_templates[sid]
 		if(!roundstart_template)
 			CRASH("json_key:[json_key] value \[[sid]\] resulted in a null shuttle template for [src]")